1. Field of the Invention
The present invention relates to a tray-out control method for moving out a loading tray of an optical drive, and more particularly, to a method for controlling a tray-out force according to whether an optical disk is placed on the loading tray.
2. Description of the Prior Art
Please refer to FIG. 1, which is a schematic diagram showing a spindle motor, a loading tray, and a clamping device installed in an optical drive. The optical drive includes the spindle motor 10, the loading tray 20, and the clamping device 40. The loading tray 20 can be used to hold an optical disk 30, and the loading tray 20 further includes a plurality of tabs 25. When the optical drive is vertically arranged, the tabs 25 can be used to help keep the optical disk 30 steady, so that the optical disk 30 will not drop out from the loading tray 20.
Please refer to FIG. 2. When the optical disk 30 is placed on the loading tray 20 and the loading tray 20 is moved into the optical drive (tray-in), the spindle motor 10 will rise and support the optical disk 30. Because the spindle motor 10 is embedded with a magnetic material (not shown) and the clamping device 40 is also embedded with a permanent magnet (not shown), the permanent magnet embedded in the clamping device 40 will be attracted by the magnetic material in the spindle motor 10 after the spindle motor 10 rising to an appropriate position. Therefore, the clamping device 40 and the spindle motor 10 can fix the optical disk 30, and the spindle motor 10 will rotate the optical disk 30 to proceed with data-search or data-access operations.
Please refer to FIG. 3. Similarly, if the loading tray 20 is moved into the optical drive (tray-in) without the optical disk 30, the spindle motor 10 will still rise and attract the permanent magnet in the clamping device 40, so that the clamping device 40 and the spindle motor 10 will be in contact with each other.
Whether the optical disk 30 is placed on the loading tray 20 or not, the spindle motor 10 will rise and attract the clamping device 40 after the loading tray 20 moves into the optical drive. When the loading tray 20 moves out (tray-out), the spindle motor 10 will descend to separate the spindle motor 10 and clamping device 40 so that the loading tray 20 can move out of the optical drive. As shown in FIG. 2, when the optical disk 30 is placed on the loading tray 20, a space will exist between the clamping device 40 and the spindle motor 10. Because the optical disk 30 is placed between the clamping device 40 and the spindle motor 10, the magnetic attraction is diminished. As shown in FIG. 3, when the loading tray 20 is not placed with the optical disk 30, the clamping device 40 and the spindle motor 10 are closely in contact with each other and the magnetic attraction between the clamping device 40 and the spindle motor 10 is strengthened.
When the loading tray 20 moves out, the force applied to the loading tray 20 must overcome the strengthened magnetic attraction for separating the closely contacted spindle motor 10 and the clamping device 40. If the loading tray 20 is placed with the optical disk 30, the magnetic attraction is lower and the same face described above moves loading tray 20 will vibrate more seriously.
According to the prior art, when the optical drive is horizontally arranged and the loading tray 20 is placed with the optical disk 30, the vibration of the loading tray 20 will not lead to harmful impacts. However, when the optical drive is vertically arranged and the loading tray 20 is placed with the optical disk 30, the vibration of the loading tray will cause the tabs 25 of the loading tray 20 to be unable to hold the optical disk 30 when the loading tray 20 moves out by applying the same force. Afterwards, the optical disk 30 will drop and be damaged.
If the tray-out force applied to the loading tray 20 diminishes, the tray-out force may not overcome the magnetic attraction so that the loading tray 20 may not successfully move out.